Chapter 10 Distribution and significance of basaltic eruptive centres: São Miguel, Azores

摘要: Abstract Basaltic volcanism occurs at all the active volcanic systems of Sao Miguel. For last 30 ka, eruption basaltic magma has been particularly significant in areas between three polygenetic volcanoes – Sete Cidades, Fogo and Furnas two fields have developed: Picos Fissural Volcanic System (PFVS) Congro (CFVS). About 5 ka ago activity CFVS ended abruptly since then almost concentrated PFVS, where about eruptions taken place. Despite absence eruptive activity, system represents one most seismic archipelago. It shows episodes deformation that are indicative ascent, which halted beneath system. Two historical associated with PFVS. The 1563 Pico do Sapateiro was composition, whereas 1652 was, for centuries, also considered to be basaltic. This event had, however, a Vulcanian style involved production large amounts fine ash growth trachyte domes coulees. accurately described contemporary accounts.